Course indicator



July 24, 1951 L. F. BEACH ETAL 2,561,332

COURSE INDICATOR OIgnalvF'iled Feb. 20, 1942 INVENTORS- L .E BEACH O.E.ESVAL -B z, LANE M l' RNEY,

Patented ]uly 24, 1951 COURSE INDICATOR Lennox Beach, 'Port Washington, Orland E.

Esval, Huntington, and Arthur Lame, Roosevelt, N. Y., assigner-s to TheSperryCorporation, a corporation of Delaware riginal application February 20,`194'2,"Scrial No. 431,704. Divided and this `application March 31, 1945, Serial No.1585,852

12 claims. l

V-I'his .invention generally .relates to azimuth or .course indicators of a character particularly adapted for .use with directional gyros either of the free or slaved (gym-magnetic) type. More particularly, the present invention is directed to the novel subject matter in this connection divided from our copending application Serial No. 431,794, iiled February 120, 1942 for Directional Gyroscope, which has now matured into U. S. Patent 2,406,341 issued on August 27, 1946.

The novel features and details of the invention 'will be apparent from the following descripvtion when read in relation with the accompanying drawing, wherein Fig. l is a front elevation showing the front of a -directional gyro having the improved course or azimuth indicator incorporated therein;

Fig. 2 is an enlarged 4side elevation "of the instrinnent shown in Fig. v1 with a portion of its housing broken away and with some of the interior parts illustrated invertical section;

Fig. 3 isa detail view vof the preferred form of said indicator vforming the subject matter of the present invention;

Fig. 4 is a front elevation showing the front nf s. directional gyro having .a modied form of azimuth indicator therein; .and

Fig. V5 is a vertical section of ythe .gyro Vinstrument shown in Fig. v4 in which only :sutlici'ent of `the :same is shown to illustrate the form of the modified type of indicator.

The yinstrument'with which the improved indicator isillustrated in the drawings is 'a directional-gyro voi v.the type that may or maynot loe slaved to or :controlled from a remote magnetic compass. As shown in Figs. 1 and 2, the directional rgyro 'includes a housing a5 having a iront Wall t with fa window 1 therein through which the improved indicator is observed. `The indicator or .improved compass `card of the `present invention iis desig- :cated at 8. Card 8 Vis shown in the drawing as mounted on a .shafts that turns in ailxed bushing the housing 5. The shaft 9 and consequently the card is positioned in the housing 5 by :means of the vertical ring I yI of lthe 7gyro instruinent which :drives `the same through the bevvrei-igear I2 at the hase .of 'the ring and the crown :gear t3. Ring II of the fgyro instrument is suitably mounted to move about a vertical axis Within the housing :5, the :same 'supporting a conventyne of .gyro rotor case whose Arotor is :suitably spun about a normally horizontal axis.

Card f8 in the form .of the invention shown in .l and L2 is illustrated as .a ilfat disc Shaving teeth Ail! Lat its .periphery that 'mesh with a gear 'lon .shaft 9- positioned :by a setting knob I5. A .suitableslip friction connection 4e may be employed between 4the card and shaft 9 to permit the card to ybe turned relative to vthe shaft by the knob I 5.

With `reference to Fig. 3, thefazimu-th indicating card .i8 is shown to include two yiridepernient sets of concentric scales I'I :and t8 calibrated to readin degrees of a circle. The outer scale YII is of langer radius than the rinner scale -I8. Mask I'S is fixed in `position behind the Window 1, the -same overlying the card 8 .and concealing from view :all .but a range of :each scale hav-ing vdesignated calibrations of different values. The cut 'out at'thc-top of the mask indicated at '.Zil iscircuiar in .form to conceal .scale I8 from View While exposing :a desired rangev of values of scaleqfl'l. The opening at the .lower part .oi the vmask vindiycated at ,I2-I is smaller than cut Iout 2t), being closer to the center vof the circular card 8. `Opening 2f| iinthemask Iiconcealsscale I1 'and exposesade- .siredgrange of values `of scale I8. 'Ihemask consequen-tly provides ,separate openings for exposing portions of the respective scales on the card. Scale `ill in connection with lubber line 22. Scale :I8 is read in .connection with lubber line .23. With this type of card, it will be understood that `.the .scale Iz'I 4and lufbber line'22 indicate the course or heading of the dirigible craft .in which the instmment is employed. Scale :I8 and iubber :li-ne 13 provide 'an indication that is the reverse Aof that indicated by the main scale. Consequently before executing a procedure turn of 18.0, the pilot .observes the bottom :dial .of the instrument, 1i. e., fscale IB, to 'ascertain what the course .or heading v.reading should be on scale I1 when Athe turn is completed. The vcraft is 4then turned until the proper lvalu-e on :scale il reaches vthe lubber `line?? to .compl-ete theturn. The calibrations :of each'rof'the scales .ITI and VIES are readable in .an

-upright aand 'non-inverted .position in relation to these respective lubber lines $22 and .23. Mask 119 -exposesrranges .of the respective scales yof the card tend through .a :range of from 0 to 360 have corresponding radial designations With adjacent nu- .meral's of like values that :are .inverted relative one another to appear .in :a readable position at thearespectlye opening-s in :the mask.

-' `lfithitlie azimuth indicator card or .compass .card f8, .there :is valso employed, the vpresent stance, a .course indicating element d@ mounted tarotate about :an axis ycoaxial with 1that :of :sa-id :compass card and :preferably .rotatably mounted A suitable resilient coupling Vmember 50 is provided to frictionally connect course tndicating element 40 with the compass card 8 so that they both normally rotate together but may, when desired, be relatively rotated as shown. The course indicating element 40 comprises a disc having a toothed periphery that may be engaged with a gear 4I connected to a suitable courseindicator setting knob 4 I. The visible portion of course indicating element 40 comprises an index in the form of the parallel lines 42 indicated in Fig. 1. As stated above, the course indicating element 40 normally rotates with the compass card 8 through the frictional engagement therebetween provided by coupling member 50 to thereby continuously indicate on said card a particular course. When it is desired to indicate a new heading or course, the course indicating element 40 is manually rotated by knob 4I and gear 4| relative to the card 8 until the parallel lines 42 embrace the desired new course calibration. When so actuated the `parallel lines of the course indicating element move across both scales l1 and I8 and the openings in the mask. With the craft on the desired new course, say north or the lines 42 of the course indicating element 40 assume the position indicated in Fig. 1 in which the parallel lines 42 thereof embrace or are on opposite sides of the lubber line 22.

In the modification of the invention shown in Figs. 4 and 5, the compass card indicated at 25 is illustrated as directly mounted on the vertical' ring 26 of the directional gyroscope. In this instance, the card 25 is ring shaped and includes on its exterior face two circular scales 2l and 28, respectively, whose values are arranged in 180 spaced relation. As shown in Fig. 4, the mask 30 for this type of card includes two rectangular openings 3| and 32 which respectively expose the top and lower scales on the card. The lubber lines for each of the scales in this form of card are indicated at 33 and 34. The top opening 3l in the mask 30 is made larger than opening 32 therein in order to indicate the primary scale of the instrument.

Since many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. In an indicator, a compass card comprising two azimuth indicating scales each calibrated to read in degrees of a circle, a mask Xed in position overlying said scales and arranged to conceal all but a `portion of eac-h of said scales having designated values 180 apart respectively, the exposed calibration designations of each scale being readable in an upright position, and a lubber line for each of said scales.

2. In a course indicator, a compass card comprising two azimuth indicating scales each calibrated to read in degrees of a circle, a mask xed in position overlying said scales and having separate openings therein for the respective scales, said mask and the openings therein being so arranged relative to the scales as to conceal all but a relatively small portion of each of said scales having designated values of a predetermined number of degrees apart, respectively, the calibration designations of each scale being readable in an upright position when in registry with the mask openings, and a lubber line at each of the mask openings.

3. In a course indicator, a compass card comprising two azimuth indicating scales each calibrated to read throughout 360, a mask fixed in position overlying said scales and having separate openings therein for the respective scales, said mask and the openings therein being so arranged relative to the scales as to conceal all but a relatively small portion of each of said scales having designated values apart, respectively, the calibration designations of each scale being readable in an upright position when in registry with the mask openings, and a lubber line at each of the mask openings.

4. In an indicator, a compass card comprising two azimuth indicating scales each calibrated to read throughout 360, said scales being rotatable as a unit and means for rotatably Supporting them, a mask fixed in position overlying said scales and having openings therein so arranged relative to said scales as to conceal all but a relatively small portion of each of said scales having designated values 180 apart respectively, the calibration designations of each scale being readable in an upright position when in registry with the mask openings, and a lubber line at each of the mask openings.

2i. In a course indicator, a disc-like compass card having two circular, azimuth indicating scales thereon each calibrated to read throughout 350, means for rotatably supporting said card, said scales being concentrically arranged with adjacent calibration designations of the respective scales of like values but inverted with respect to each other, a n iask having separate openings therein for concealing all but a relatively small portion of the respective scales, said openings being arranged in 180 spaced relation and relative to the scales so as to expose calibration designations of each scale simultaneously that are readable in an upright position, and a lubber line at each mask opening.

6. In a course indicator, a compass card comprising two azimuth indicating scales each calibrated to read throughout 360, means for rotatably supporting said card, each of said scales being arranged on the surface of a cylinder to turn together and with the designations of substantially aligned calibrations of the respective scales of values dinering by 180, a mask fixed in position overlying said scales and having separate openings therein for concealing all but a relatively small portion of the respective scales, said openings being arranged to expose substantially aligned calibrations of both scales simultaneously, and a lubber line tor each of said scales.

7. In an indicator, a compass card comprising two azimuth indicating scales each calibrated to read in degrees of a circle, a mask fixed in position overlying said scales and arranged to conceal all but a comparatively small portion of each of said scales having designated values 180 apart, respectively, the calibration designations of each scale being readable in an upright position when exposed to view by said mask, said mask exposing one scale to a greater extent than the other whereby to afford a ready distinction therebetween, and a lubber line for each ofsaid scales.

8. In an indicator, a disc-like compass card, means for pivotally supporting said card to rotate in a vertical plane about a normally horizontal axis, said card comprising two scales each calibrated to read in degrees of a circle, a mask arranged to conceal all but a limited portion of each of said scales, the calibrations of one range so exposed having designated values differing a predetermined number of degrees from those of the other exposed portion, each scale being readable in an upright position when so exposed to View, and a lubber line for each of said scales.

9. In a course indicator, a compass card comprising two azimuth indicating scales each calibrated to read in degrees of a circle, a mask arranged in xed position overlying said scales and having separate openings therein for the respective scales, said mask and the openings therein being so arranged relative to the scales as to conceal all but a relatively small portion of each of said scales having designated values of a predetermined number of degrees apart, respectively, the calibration designations of each scale being readable in an upright position when in registry with the mask openings. a lubber line at each of the mask openings, and a course setting element frictionally engaged with the card.

10. In an indicator, the combination with a compass card having a circular series of scale graduations and two concentric, circular series of direction-indicating numerals associated therewith, each series covering the range of from 0 to 360, radially corresponding and adjacent numerals of the respective scales being of like values but inverted with respect to each other, of a mask having separate openings therein for concealing all but a relatively small portion of the respective series of numerals, said openings being arranged in 180 spaced relation and relative to the scales so as to simultaneously expose numerals of both series when in upright and non-inverted relation, and a lubber line at each mask opening.

11. In an indicator, a compass card comprising two azimuth indicating scales each calibrated to read in degrees of a circle, a mask fixed in position overlying said scales and arranged to conceal all but a portion of each of said scales having designated values 180 apart respectively, the exposed calibration designations of each scale being readable in an upright position, a lubber line for each of said scales, a course indicating element movable over and readable on both the scales of said compass card, a resilient coupling member frictionally connecting said element and said card whereby said element is movable with 'y Number said card but may be movable relative thereto, and manually operable means for positioning said element relative to said card whereby said element may be manually reset at will to indicate any desired course on both scales without disturbing the position of the compass card.

12. In an indicator, the combination with a directional gyro, a compass card comprising two azimuth indicating scales calibrated to read in degrees of a circle, each of said scales having designated values apart and each being readable in an upright position, a course indicating element mounted to rotate about said axis and movable over and readable on both scales on said compass card, a resilient coupling member frictionally connecting said element and said card whereby said element will rotate with said card but may be rotated relative thereto, and manually operable means for rotating said element relative to said card whereby said element may be manually reset at will to indicate any desired course while the relation of the gyro to the compass card remains undisturbed.

LENNOX F. BEACH. ORLAND E. ESVAL. ARTHUR W. LANE.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Name Date MacGahan Mar. 5, 1918 Humphreys July 11, 1922 Tracy Jan. 14, 1930 Sperry, Jr Sept. 18, 1934 Browne Mar. 29, 1938 Carbonara Aug. 23, 1938 McCleary May 16, 1939 Meredith Nov. 9, 1943 Olshwsky Dec. 7, 1943 Cocks Aug. 28, 1945 FOREIGN PATENTS Country Date Great Britain Apr. 12, 1928 Germany May 7, 1918 Germany Dec. 12, 1922 Number 

